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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS
GCE Advanced Level and GCE Advanced Subsidiary Level
MARK SCHEME for the May/June 2006 question paper
9702 PHYSICS
9702/04
Paper 4
Maximum raw mark 60
This mark scheme is published as an aid to teachers and students, to indicate the requirements of the
examination. It shows the basis on which Examiners were initially instructed to award marks. It does
not indicate the details of the discussions that took place at an Examiners’ meeting before marking
began. Any substantial changes to the mark scheme that arose from these discussions will be
recorded in the published Report on the Examination.
All Examiners are instructed that alternative correct answers and unexpected approaches in
candidates’ scripts must be given marks that fairly reflect the relevant knowledge and skills
demonstrated.
Mark schemes must be read in conjunction with the question papers and the Report on the
Examination.
The minimum marks in these components needed for various grades were previously published with
these mark schemes, but are now instead included in the Report on the Examination for this session.
•
CIE will not enter into discussion or correspondence in connection with these mark schemes.
CIE is publishing the mark schemes for the May/June 2006 question papers for most IGCSE and
GCE Advanced Level and Advanced Subsidiary Level syllabuses and some Ordinary Level
syllabuses.
www.xtremepapers.net
www.studyguide.pk
Page 1
1
Mark Scheme
GCE A/AS Level – May/June 2006
Syllabus
9702
(a) centripetal force is provided by gravitational force
mv2 / r = GMm / r2
hence v = √(GM / r)
B1
B1
A0
[2]
(b) (i) EK (= ½mv2) = GMm / 2r
B1
[1]
(ii) EP = - GMm / r
B1
[1]
(iii) ET = - GMm / r + GMm / 2r
= - GMm / 2r.
C1
A1
[2]
M1
A1
[2]
M1
A1
[2]
(a) e.g. fixed mass/ amount of gas
ideal gas
(any two, 1 each)
B2
[2]
(b) (i) n = pV / RT
= (2.5 × 107 × 4.00 × 104 x 10-6) / (8.31 × 290)
= 415 mol
C1
C1
A1
[3]
C1
C1
A1
[3]
(a) gradient of graph is (a measure of) the sensitivity
the gradient varies with temperature
M1
A1
[2]
(b) 2040 ± 20 Ω corresponds to 15.0 ± 0.2 °C
T / K = T / °C + 273.15 (allow 273.2)
temperature is 288.2 K
C1
C1
A1
[3]
(a) (i) 1.0
B1
[1]
B1
[1]
(c) (i) if ET decreases then - GMm / 2r becomes more negative
or GMm / 2r becomes larger
so r decreases
(ii) EK = GMm / 2r and r decreases
so (EK and) v increases
2
(ii) volume of gas at 1.85 × 105 Pa = (2.5 × 107 × 4.00 × 104) / (1.85 × 105)
= 5.41 × 106 cm3
6
4
so, 5.41 × 10 = 4.00 × 10 + 7.24 × 103 N
N = 741
(answer 740 or fails to allow for gas in cylinder, max 2/3)
3
4
Paper
04
(ii) 40 Hz
(b) (i) speed = 2πfa
= 2π × 40 × 42 × 10-3
= 10.6 m s-1
(ii) acceleration = 4π2f2 a
= (80π)2 × 42 × 10-3
= 2650 m s-2
(c) (i) S marked correctly (on ‘horizontal line through centre of wheel)
(ii) A marked correctly (on ‘vertical line’ through centre of wheel)
© University of Cambridge International Examinations 2006
www.xtremepapers.net
C1
A1
[2]
C1
A1
[2]
B1
B1
[2]
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Page 2
5
Mark Scheme
GCE A/AS Level – May/June 2006
Syllabus
9702
(a) (i) force per unit positive charge (ratio idea essential)
B1
[1]
(ii) E = Q / 4πε0r2
ε0 being the permittivity of free space
M1
A1
[2]
(b) (i) 2.0 × 106 = Q / (4π × 8.85 × 10-12 × 0.352)
Q = 2.7 × 10-5 C
C1
A1
[2]
C1
A1
[2]
(ii) V = (2.7 × 10-5) / (4π × 8.85 × 10-12 × 0.35)
= 7.0 × 105 V
6
(c) electrons are stripped off the atoms
electrons and positive ions move in opposite directions,
(giving rise to a current)
B1
(a) (i) arrow B in correct direction (down the page)
B1
(ii) arrow F in correct direction (towards Y)
B1
[2]
B1
[1]
B1
[1]
(c) suggested reasonable values of I and d
mention of expression F = BIL
force between wires is small
compared to weight of wire
B1
B1
M1
A1
[4]
(a) ‘uniform’ distribution
B1
[1]
(b) concentric rings
B1
[1]
(c) higher speed, more momentum
λ=h/p
so λ decreases and ring diameter decreases
M1
M1
A1
[3]
(a) arrow labelled E pointing down the page
B1
[1]
(b) (i) Bqv = qE
forces are independent of mass and charge ‘cancels’
so no deviation
M1
M1
A1
[3]
M1
M1
A1
[3]
(b) (i) When two bodies interact, force on one body is equal but opposite in
direction to force on the other body.
(ii) direction opposite to that in (a)(ii)
7
8
Paper
04
(ii) magnetic force > electric force
so deflects
‘downwards’
© University of Cambridge International Examinations 2006
www.xtremepapers.net
B1
[2]